If Rafe comes back she'll be splitting up her kids from each other because she won't be living in the mansion any more and her kids will no longer have their parents under the same roof and Sami will have to go back to sharing custody.

Two of her kids already don't have their parents under the same roof, a little fact that keeps getting swept under the rug and which makes this contrived move into DiMansion even more irritating than it would already be to me. If Will and Allie have feelings and desires to have the same nuclear family unit Sami herself always dreamed of then too bad for them, apparently.